Communication Control Device, Communication Control Method, and Terminal Device

1. A communication control device comprising: circuitry configured to control base stations of one or more small cells which are partly or entirely overlapped by a macrocell to transmit signals for measurement by a terminal device and decide a timing at which each of the signals is transmitted in accordance with a time taken for a corresponding one of the base stations to be activated from an idle state; transmit small cell information to the terminal device, the small cell information comprising a list including the timing at which each of the signals is transmitted and information that indicates a frequency channel at which each of the signals is transmitted; acquire a result of the measurement performed by the terminal device with regard to said one or more small cells; and select a base station which is not to be set in the idle state from base stations of the one or more small cells based on the result of the measurement.

2. The communication control device according to claim 1 , wherein the one or more small cells are small cells selected based on position information which indicates a position of the terminal device.

3. The communication control device according to claim 1 , wherein the circuitry is further configured to control the base stations of the one or more small cells; and refrain from causing the selected base station to be in the idle state, and cause a base station other than the selected base station among the base stations of the one or more small cells to be in the idle state.

4. The communication control device according to claim 1 , wherein each of the signals for the measurement is a reference signal.

5. The communication control device according to claim 1 , wherein the result of the measurement includes information regarding reception power or quality of a signal for the measurement.

6. The communication control device according to claim 1 , wherein the result of the measurement is information regarding part of the one or more small cells.

7. The communication control device according to claim 1 , wherein, when reception power or quality of a signal for the measurement with regard to all of the one or more small cells does not exceed a predetermined threshold value, the result of the measurement includes information which indicates that the reception power or the quality with regard to all of the small cells does not exceed the predetermined threshold value.

8. The communication control device according to claim 1 , wherein the circuitry is configured to select the base station that is not to be set in the idle state when notification of a demand for performing radio communication in a small cell is given by the terminal device.

9. The communication control device according to claim 1 , wherein the terminal device is able to perform radio communication using one principal frequency band and one or more auxiliary frequency bands, and wherein the circuitry is further configured to control the terminal device to use a frequency band for the macrocell as the one principal frequency band and to use a frequency band for the small cell of the selected base station as one of the one or more auxiliary frequency bands.

10. A communication control method comprising: controlling base stations of one or more small cells which are partly or entirely overlapped by a macrocell to transmit signals for measurement by a terminal device and deciding a timing at which each of the signals is transmitted in accordance with a time taken for a corresponding one of the base stations to be activated from an idle state; transmitting small cell information to the terminal device, the small cell information comprising a list including the timing at which each of the signals is transmitted and information that indicates a frequency channel at which each of the signals is transmitted; acquiring a result of the measurement performed by the terminal device with regard to said one or more small cells; and selecting, using a processor, a base station which is not to be set in the idle state from base stations of the one or more small cells based on the result of the measurement.

11. A communication control device comprising: circuitry configured to control transmission of a signal for measurement performed by a terminal device with regard to a small cell which is partly or entirely overlapped by a macrocell and decide a timing at which the signal is transmitted in accordance with a time taken for a base station of the small cell to be activated from an idle state; transmit small cell information to the terminal device, the small cell information comprising a list including the timing of the signal and information that indicates a frequency channel at which the signal is transmitted; and refrain from causing the base station of the small cell to be in an idle state when the base station of the small cell is selected as a base station that is not to be set in the idle state based on a result of the measurement.

12. A terminal device comprising: circuitry configured to receive signals from base stations of one or more small cells which are partly or entirely overlapped by a macrocell, each of the signals being received at a timing decided in accordance with a time taken for a corresponding one of the base stations to be activated from an idle state; receive small cell information comprising a list including the timing at which each of the signals is received and information that indicates a frequency channel at which each of the signals is transmitted; determine a result of measurement with regard to the one or more small cells; and provide the result of the measurement to a communication control device which selects a base station which is not to be set in the idle state from the base stations of the one or more small cells based on the result of the measurement.